Window cranks of the general type with which this invention is concerned are well known for operating a window pivoting device located on the inside of a window. Pivoting devices typically include an axially rotatable actuator stub shaft extending from a housing within which a gear drive is located. It is common that such actuator stub shafts project outwardly and upwardly on the inside of a window, usually on the sill, and are designed to receive a removable crank. Examples of such window pivoting devices and cranks are disclosed in U.S. Pat. Nos. 5,201,241 and 5,168,770.
It is also known to design window cranks to be pivotable between an operating position where they can readily be turned by hand to rotate the actuator shaft and a retracted position folded toward the sill or window, as in the aforementioned U.S. Pat. No. 5,201,241. Retractable cranks for turning actuator shafts in devices other than window pivoting means are also conventional as disclosed in U.S. Pat. Nos. 5,230,290, 3,383,945 and 1,274,471. All of these prior art cranks are of relatively complicated design and in none of them is a crank turning arm articulated with respect to the actuator shaft and a gripping knob to provide optimum retractability.
It is a principal purpose of the present invention to provide a retractable crank specially designed for a window pivoting device which includes one abutment capable of holding a turning arm of the crank in a retracted position with its knob projecting either inwardly toward or downwardly with respect to the sill and window, but not outwardly away from the window. It is also a principal purpose of the present invention to provide another abutment capable of holding the turning arm in its operating position so that when the turning arm is directed upward it is over a dead center position from its retracted position and cannot then fall back to the retracted position.